sine function voltage input

[KHH]

Hi there,

I'm a newbie in using Labview with the 6487 picoammeter. I'm trying to characterize the electrical properties of a type of ionic conductor, silver sulfide, and need to use Labview and 6487 to do it. The task I'm working on is that I want to ramp up and down the voltage applied to the silver sulfide crystal and measure the current flowing through it, so the voltage is more like a sine wave or a triangle wave. I'm using the 6487 as both the voltage source and the current meter. Could you help me with the Labview code for this task? Any input is appreciated.


Regards,
Keng
MIE, UIUC

[Dennis_Knutson]

First, check this post for information on where you can get the driver for the instrument. Then, do a search of the LabVIEW or Instrument Control forum for the subject "sweep" or "ramp" and you should find some clues. One such post was here. This seems to be a common task for students based on how many postings there have been on the same subject.

[KHH]

Thanks Dennis,

I have already set up the instrument and been able to sweep voltage inputs for different ranges, but what I needed was to repeat the cycle for several times, and that's where I didn't know how to write code for.

Keng

[Dennis_Knutson]

Without seeing your code, all I can do is guess at what you're doing. Usually, all you need to do to repeat something is to put the existing code inside a while or for loop.

[KHH]

Hi Dennis,

This is the vi i'm using. It's modified a little from an example vi from Keithely. Could you please take a look? I appreciat it.

Regards,
Keng

[Dennis_Knutson]

All I can do is give some general comments since I don't have the instrument. You don't have any loop so in order to run it, when the VI is stopped, you have to set all of your controls first. This includes the file save button. Once the controls are set, running the VI should give you your graphs and a saved file. If you want to run it again with the same settings, you just have to click the run button. If you want different settings, make the changes and then click the run. Do not use the continuous run button on the toolbar. If you have some specific problems, what can help someone figure out the problem is for you to run the VI and then go to the Operate menu and select Make Current Values Default. Save the VI then. This will then save all of your user inputs and outputs along with the VI.

[KHH]

Thanks Dennis. It works pretty well for me.

Keng